Article continues below advertisementStassie Karanikolaou is turning up the heat!The longtime bestie of Kylie Jenner dropped a sizzling mirror selfie that had fans doing a double-take. Rocking a bold red workout set, Karanikolaou showed off her sculpted abs and famous curves in a look that screamed confidence.Article continues below advertisementSource: @staskaranikolaou/InstagramStassie Karanikolaou shared a mirror selfie in her red activewear.